Phonograph



Sept, 20,1927 B. STUMP PHONOGRAPH Filed July 29, 1922 2 Sheets-Sheet 1INVENTOR. 5. STU/WP,

ATTORNEY.

Patented Sept. 20, 1927. 4

BURDETTE STUMP, F DEhIVER, COLORADO.

,PHONOGRAPH.

Application filed July 29,

This invention relates to improvements in phonographs and its primaryobject is toproduce an instrument in which the sounds reproduced by thevibratory motion of a diaphragm actuated by the movement of a stylusthrough the grooves of a phonograph ic record, are transmitted to theear, in

clear, mellow and distinct tones. Another object of the invention is toro-- vide av phonograph in which the reproduced sounds are enhanced byreenforcemen't of the vibrations of the diaphragm, and still furtherobjects reside in details of construction and a novel arrangement'ofparts, fully set forth in the following description with reference tothe accompanying drawings.

In the drawings in the several views of which like parts are similarlydesignated,

Figure 1 represents a partially sectional front elevation of my improvedphonograph; Figure 2, a vertical'section through'the instrument,partially in elevation, takenon the line 2'2 in Figure 4; 1 I

Figure 8, a transverse,horizontal section on the line 3*3, Figure 2;

Figure 4%, a vertical section taken on the line 4-4c, Figure 2;

Figure 5, a section along the line 5+5, Figure 4: drawn to an enlargedscale;

Figure 6, a horizontal section along the line 6-6, Figure 4; and iFigure 7, a fragmentary section 'on the line-77, Figure 4.

The most important and essential feature of the invention resides intheprovisioh of a hollow metallic element which is connected with avibratory sounding board over which the sound waves move while'beingpropagated through the air; another feature is to so arrange the conduitthrough which the sound produced by the vibrating diaphragm, passes tothe tone-chamber of which the sounding board is a part,that the motionof each sound wave is transmitted to the walls of the chamber andthrough said walls to certain auxiliary metal elements which bysympathetic vibration aid in its amplification and purification; andstill another fea ture is to provide means for limiting the vibratorymotion of the walls of the instrument and thereby steady and sustain thetones produced therein by weight and advantageously appliedreenforcements.

Referring now to the drawings, the reference character 2 designates aphonograph casing or cabinet of conventional size and 1922, SeriaI No.578,347.

form whichby means of partitions 3, 4i and 5 1s dlvlded into a motorchamber 6, a pr1- mary tone chamber 7' and a secondary tone" chamber 8.

. The walls of the casing are made of comparat'ively heavy wood toprevent excessive vibration, and the bottom is for the same purpose,weighted by means of ametal plate 9..

A motor 10 in the chamber 6 is operatively connected with a rotaryturntable 12 upon which the phonographic records are supported.

Arotary hollow tone arm 13 and a reproductive sound box 14: at the freeend thereof,

an elbow 18 constituting the throat of the primarytone chamber. v

The latter-is composed of four diverging sides of which the beforementioned partitionst and 3 are the upper-and lower ones.

An upright partition 19 inxthe rear end of the tone chamber provides acompartment 20in which the elbow is fitted.

It is an' important feature of the invention that thi's'elbow touchesthe four walls of the compartment as clearly shown in Figure 5, since bythese means the vibrations of the sound waves are communicated to thewalls 'of the chamber and indirectly to the walls'of the cabinet. i

The partition 19 has an-opening to receive the open 'end'of the metalthroat and the latter is formed with a number of flutes or corrugations18 as best shown in Figure 5, which'give direction to the tone wavesalid'prevent them fromcrowding or blending together. i

Y The lower wall 3 of the tone chamber is loose at its forward edge andconstitutes a the record to reproduce excessive vibration and sustainsand steadies the tones as they pass through the metal throat, and asimilar plate 22 is placed inside the motor chamber between thepartitions 4 and 5 for the same purpose.

The funnel-shaped primary sounding chamber, the upright sides of whichare designated by the numerals 23 and 24, is open at the front of thecasing and its opening may, if so desired, be covered by a nonmetallicornamental screen 25.

Loosely suspended from the lower side 3 or sounding board of the primarysounding chamber inside the lower and secondary chamber, is a hollowmetal vessel 26 which in the construction shown in the drawings, is madein the form of a cylindrical kettle. The vessel is suspended from a hookin the center of the sounding board by means of a non-metallic strap 27,preferably made of leather, and its movement is restricted by.

two spiral springs 28 which connect its bottom portion at diametricallyopposite points, with the side walls of the casing.

hen in the operation of the instrument, the sounding board vibrates bythe tone waves propagated from the throat through the gradually wideningtone chamber, its motions are transmitted to .the metal vessel whichbeing capable of independent vibration, enhances the sound, and greatlyimproves the character of the tones by a meltion of foreign noises.

An inverted gong 29 supported on the bottom of the vessel serves toadapt it to instrulowing and separative effect and the absorpmentsof'difi'erent sizes and tone-reproducing qualities. it having been foundthat by varying the size of this gong or by placing two or more on thesame support, the vessel may be attuned to any instrument.

It is essential thatthe hollow metal body be suspended from the lowerwall of the tone chamber, free for independent vibration and through themedium of a non-me tallio member which prevents diffusion of thetransmitted tones.

It will be evident that the tone waves passing through the throat of thetone chamher not only vibrate the walls thereof by their direct contactwith the throat but also indirectly vibrate the walls of the casing.These vibrations are taken advantage of to further improve the characterof the reproduced sounds, by equipping the walls with metallic resonantelements, of a type similar to that connected with the bottom of thetone chamber.

These elements may be of different form,

construction and proportions, according to the size and character of theinstrument to which they are applied and it should be understood thattheir design and arrangement as shown in the drawings, may be varied toaccord with different instruments. without departing from the spirit ofmy invention.

In the drawing, two bells 30, a gong 31. an aperturedtube 32 and aspiral spring 33 are connected with the rear wall of the instrument, itbeing apparent that the spring.

performs to some extent the function of a hollow body.

A gong 34 is fastened to one of the side walls of the cabinet. a doublegong 35 is applied to the opposite wall of the same, a similararrangement of gongs 36 is attached to the upper wall of the primarytone chamber inside the motor chamber and a pair of heavier gongs 37 issupported on the heavy metal-weighted bottom of the casing, which isless' subiect to vibration.

Aside from their purifying, amplifying and mellowingeffect upon thesound waves produced in the operation of the instrument, the difierentparts and features of construction hereinabove described, co-operate toseparate and classify the tones and thereby prevent the undue blendingand unharmonious mingling often observed in phonograph instruments ofordinary construction.

Having thus described my improve-d phonograph, I desire it understoodthat varia-. tions in the arrangement and construction of itsco-operative parts, other than those hereinbefore referred to, may beresorted to within the. scope of my invention, as defined bylthehereunto appended claim. b

What I claim and desireto secure by Letters Patent is: i

In a phonograph,a cabinetprovided in its upper portion with a tonechamber eXtending from frontto rear and taper-ed longitudinally, saidtone chamber being composed of top, bottomand side walls, the bottomwall having its front edge free and constituting a sounding board, aresonator consisting of an open cylindrical metallic vessel suspended atits open end from the bottom wall of the tone chamber andarranged inspaced relation with the walls and bottom of the cabinet, and oppositespiral springs connecting theclosed bottom of the resonator with thewalls of the cabinetat diametrical- 1y opposite points.

In testimony whereof I have aflixed my signature.

BURDETTE sTuMP.

